Prospective Diary Study of Nonpainful and Painful Phantom Sensations in a Preselected Sample of Child and Adolescent Amputees Reporting Phantom Limbs

Age and Sex Differences in Pediatric Neuropathic Pain and Complex Regional Pain Syndrome: A Scoping Review

BACKGROUND

Age and sex differences may exist in the frequency (incidence, prevalence) or symptoms of neuropathic pain (NP) and complex regional pain syndrome (CRPS) due to biopsychosocial factors (eg, neurodevelopment, physiological and hormonal changes, psychosocial differences) that evolve through childhood and adolescence. Age and sex differences may have implications for evaluating screening and diagnostic tools and treatment interventions.

OBJECTIVE

To map the existing literature on pediatric NP and CRPS with respect to age and sex distributions, and age and sex differences in symptomology and frequency.

METHODS

A scoping literature review was conducted. Databases were searched from inception to January 2023. Data were collected on study design, setting, demographics, and age and sex differences in frequency and symptoms.

RESULTS

Eighty-seven studies were included. Distribution of participants with CRPS (n=37 studies) was predominantly early adolescence (10 to 14 y) and female sex, while NP (n=42 studies) was most commonly reported throughout adolescence (10 to 19 y) in both sexes. Forty-one studies examined age and sex differences in frequency; 6 studies reported higher frequency in adolescence. Very few studies (n=11) examined differences in symptomology.

DISCUSSION

Large epidemiological studies are required to further understand age and sex differences in frequency of pediatric NP and CRPS. Age and sex differences must be considered when evaluating screening and diagnostic tools and treatment interventions to ensure relevance and validity to both sexes and across ages. Validated tools will improve understanding of age-dependent and sex-dependent differences in symptoms, pathophysiology, and psychosocial impact of pediatric NP and CRPS.

Prevalence of Phantom Phenomena in Congenital and Early-Life Amputees

Phantom limb pain (PLP) is a common consequence of the amputation of a limb. Persons with congenital limb absence (congenital amputees) or an acquired limb amputation at an early age seem to rarely experience PLP. However, the number of available studies and their sample sizes are low. In the present cross-sectional study, we assessed the presence of several phantom phenomena in a sample of 99 adult unilateral congenital amputees (con) of whom 34 had a limb correction later in life (limbc) and 153 adult participants with a unilateral amputation before the age of 6 years (subgroups: amputation between birth and 2 years (0-2y; n = 48), 3-4 years (3-4y; n = 46), and 5 to 6 years (5-6y; n = 59)). We found a higher prevalence and intensity of PLP in the 5-6y group compared to the other groups. Residual limb pain (RLP) intensity was higher in the 3 to 4 y and 5 to 6 y groups compared to the con group. Non-painful phantom limb sensation (PLS) intensity and telescoping intensity were higher in the 5 to 6 y group compared to the con and 0 to 2 y groups. Our results indicate that PLP prevalence as well as intensity is low when the limb loss happened before the age of 5 years. PERSPECTIVE: The prevalence of phantom limb pain, residual limb pain, and non-painful phantom limb sensation in congenital amputees and participants with an amputation early in life is low. This might be due to the missing or reduced nociceptive input from the residual limb to the brain and higher development-associated adaptability of the somatosensory system.

Deep brain stimulation for phantom limb pain

Phantom limb pain is a rare cause of chronic pain in children but it is associated with extremely refractory pain and disability. The reason for limb amputation is often due to treatment for cancer or trauma and it has a lower incidence compared to adults. The mechanism of why phantom pain exists remains uncertain and may be a result of cortical reorganisation as well as ectopic peripheral input. Treatment is aimed at reducing both symptoms as well as managing pain related disability and functional restoration. Neuromodulatory approaches using deep brain stimulation for phantom limb pain is reserved for only the most refractory cases. The targets for brain stimulation include the thalamic nuclei and motor cortex. Novel targets such as the anterior cingulate cortex remain experimental as cases of serious adverse effects such as seziures have limited their widespread uptake. A multidisciplinary approach is crucial to successful rehabilitation using a biopsychosocial pain management approach.

AAAPT Diagnostic Criteria for Acute Neuropathic Pain

OBJECTIVE

Acute neuropathic pain is a significant diagnostic challenge, and it is closely related to our understanding of both acute pain and neuropathic pain. Diagnostic criteria for acute neuropathic pain should reflect our mechanistic understanding and provide a framework for research on and treatment of these complex pain conditions.

METHODS

The Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks (ACTTION) public-private partnership with the U.S. Food and Drug Administration (FDA), the American Pain Society (APS), and the American Academy of Pain Medicine (AAPM) collaborated to develop the ACTTION-APS-AAPM Pain Taxonomy (AAAPT) for acute pain. A working group of experts in research and clinical management of neuropathic pain was convened. Group members used literature review and expert opinion to develop diagnostic criteria for acute neuropathic pain, as well as three specific examples of acute neuropathic pain conditions, using the five dimensions of the AAAPT classification of acute pain.

RESULTS

AAAPT diagnostic criteria for acute neuropathic pain are presented. Application of these criteria to three specific conditions (pain related to herpes zoster, chemotherapy, and limb amputation) illustrates the spectrum of acute neuropathic pain and highlights unique features of each condition.

CONCLUSIONS

The proposed AAAPT diagnostic criteria for acute neuropathic pain can be applied to various acute neuropathic pain conditions. Both the general and condition-specific criteria may guide future research, assessment, and management of acute neuropathic pain.

Gabapentin for phantom limb pain after amputation in pediatric oncology: a systematic review protocol

BACKGROUND

Phantom limb pain (PLP) is a prevalent problem for children after amputation because of the chemotherapy treatment. Gabapentin is a potential option to manage PLP after amputation in pediatric oncology. However, no systematic review specifically investigated this topic. Thus, this study aims to appraise the efficacy and safety of gabapentin for post-amputation PLP in pediatric oncology.

METHODS

Electronic databases (Cochrane Library, MEDLINE, EMBASE, Web of Science, CINAHL, PsychINFO, Scopus, WANGFANG, and Chinese Biomedical Literature Database) will be systematically searched from the beginning to the present without limitations to publication status and language. Primary outcome is pain intensity. Secondary outcomes are analgesic drug consumption, sleep quality, depression, anxiety, health-related quality of life, and adverse events. The treatment effect of all dichotomous outcome data will be estimated as risk ratio and 95% confidence intervals (CIs) and that of continuous outcome data will be calculated as mean difference or standardized mean difference and 95% CIs. Methodological quality of randomized controlled trials (RCTs) will be assessed using Cochrane risk of bias tool and that of case-controlled studies (CCSs) will be appraised using Newcastle-Ottawa Tool. Statistical analysis will be conducted using RevMan 5.3 software.

DISCUSSION

This study will summarize up-to-date high-quality RCTs and CCSs to assess the efficacy and safety of gabapentin for PLP after amputation in pediatric oncology. The findings of this study will help to determine whether or not gabapentin is effective and safe for children with PLP after amputation.

SYSTEMATIC REVIEW REGISTRATION

INPLASY202060090.

Effects of different anesthetic techniques on the incidence of phantom limb pain after limb amputation: a population-based retrospective cohort study

Background

General anesthesia (GA) has been considered the anesthetic technique which most frequent leads to phantom limb pain (PLP) after a limb amputation. However, these prior reports were limited by small sample sizes. The aims of this study were to evaluate the incidence of PLP according to the various anesthetic techniques used for limb amputation and also to compare the occurrence of PLP according to amputation etiology using the Korean Health Insurance Review and Assessment Service for large-scale demographic information.

Methods

The claims of patients who underwent limb amputation were reviewed by analyzing the codes used to classify standardized medical behaviors. The patients were categorized into three groups—GA, neuraxial anesthesia (NA), and peripheral nerve block (PNB)—in accordance with the anesthetic technique. The recorded diagnosis was confirmed using the diagnostic codes for PLP registered within one year after the limb amputation.

Results

Finally, 7,613 individuals were analyzed. According to the recorded diagnoses, 362 patients (4.8%) developed PLP after amputation. Among the 2,992 patients exposed to GA, 191 (6.4%) were diagnosed with PLP, whereas 121 (4.3%) of the 2,840 patients anesthetized with NA, and 50 (2.8%) of the 1,781 patients anesthetized under PNB developed PLP. The relative risks were 0.67 (95% confidence interval [CI], 0.53–0.84; P < 0.001) for NA and 0.43 (95% CI, 0.32–0.59; P < 0.001) for PNB.

Conclusions

In this retrospective cohort study, using large-scale population-based databases, the incidence rates of PLP after limb amputations were, in the order of frequency, GA, NA, and PNB.

Perspectives on Cancer Pain Assessment and Management in Children

OBJECTIVE

To report evidence regarding pain assessment and management for children and adolescents receiving treatment for cancer.

DATA SOURCES

Published research and clinical guidelines.

CONCLUSION

Children and adolescents experience multiple sources of pain across the cancer continuum. They require developmentally relevant approaches when assessing and managing pain. This review suggests that consideration of the developmental stage and age of the child are essential in both pain assessment and pain management.

IMPLICATIONS FOR NURSING PRACTICE

Pediatric oncology nurses play a key role in developmentally appropriate pain assessment, identification of potential strategies to manage pain, and delivery of pharmacologic and nonpharmacologic therapies.

Phantom Limb Pain in Pediatric Oncology

Phantom limb pain (PLP) is a prevalent problem for children and adolescents undergoing amputation due to cancer treatment. The symptoms are wide ranging from sharp to tingling. PLP in children typically lasts for a few minutes but can be almost constant and can be highly distressing. This focused review describes the characteristics, epidemiology, mechanisms, and evidence-based treatment of PLP in pediatric populations, focusing on pediatric cancer. In pediatric oncology, the administration of chemotherapy is a risk factor that potentially sensitizes the nervous system and predisposes pediatric cancer patients to develop PLP after amputation. Gabapentin, tricyclic antidepressants, opiates, nerve blocks, and epidural catheters have shown mixed success in adults and case reports document potential utility in pediatric patients. Non-pharmacologic treatments, such as mirror therapy, psychotherapy, and acupuncture have also been used in pediatric PLP with success. Prospective controlled trials are necessary to advance care for pediatric patients with PLP.

Neuropathic pain in children

Neuropathic pain (NP), due to a lesion or disease of the somatosensory nervous system, is not well documented or researched in children. NP is a clinical diagnosis that can be difficult, especially in younger children. Nevertheless, it is important to recognise NP, as pain mechanisms and consequently management and prognosis differ from other types of long-term pain. NP is common in adult pain clinics but many of the underlying disease states in which it occurs are infrequently or never encountered in paediatric practice. However, NP in childhood has been reported, even in the very young in certain clinical situations. Causes of NP include traumatic injury, complex regional pain syndrome type II, cancer and chemotherapy, chronic infection, neurological and metabolic disease, and inherited sensory nerve dysfunction. The clinical and laboratory study of traumatic peripheral nerve injury has revealed important age-related differences in clinical presentation and prognosis. It is clear that mechanisms operating during development can profoundly modify the consequences of nerve damage and NP. Clinically, diagnosis, assessment and treatment of NP are based on methods and evidence derived from data in adults. Improvements in the understanding and management of NP are likely to come from developmentally appropriate improvements in the clarity and consistency of diagnosis and systematic, well-researched approaches to treatment.

Symptoms and quality of life indicators among children with chronic medical conditions

BACKGROUND

Children with chronic conditions often experience numerous symptoms, but few research studies examine patterns of symptoms and quality of life (QoL) indicators.

OBJECTIVE

To examine if reliable latent classes of children with chronic medical conditions can be identified based on the clustering of symptoms and QoL indicators.

METHODS

Structured interviews were conducted with children ages 9-21 living with chronic medical conditions (N = 90). Multiple symptoms (e.g., pain, sleep, fatigue, and depression) and QoL indicators (e.g., life satisfaction and social support) were measured. Physical health and emotional, social, and school functioning were measured using the Pediatric Quality of Life Inventory (PedsQL). Latent class analysis was used to classify each child into a latent class whose members report similar patterns of responses.

RESULTS

A three-class solution had the best model fit. Class 1 (high-symptom group; n = 15, 16.7%) reported the most problems with symptoms and the lowest scores on the QoL indicators. Class 2 (moderate-symptom group; n = 39, 43.3%) reported moderate levels of both symptoms and QoL indicators. Class 3 (low-symptom group; n = 36, 40.0%) reported the lowest levels of symptoms and the highest scores on the QoL indicators.

CONCLUSIONS

The three latent classes identified in this study were distributed along the severity continuum. All symptoms and QoL indicators appeared to move in the same direction (e.g., worse symptoms with lower QoL). The PedsQL psychosocial health summary score (combining emotional, social, and school functioning scores) discriminated well between children with different levels of disease burden.

Phantom phenomena – Their perceived qualities and consequences from the patient’s perspective

Background and aim

The curious phenomenon phantom limbs early became the object of research, and its underlying mechanisms have been discussed over the years. The complex nature of phantom phenomena makes interpretation of the results ambiguous, regarding both prevalence and the accompanying suffering. There is a lack of knowledge about how amputees experience the meaning and consequences of phantom phenomena. The present aim, therefore, was to investigate how individuals, in an interview situation, described the qualities of possible perceived phantom phenomena, and how their experience affected their lives one month after the amputation/mastectomy.

Methods

Twenty-eight women and men who had undergone a limb amputation or mastectomy were interviewed. The focused, narrative-oriented interviews were transcribed verbatim and the scripts were analysed with content analysis.

Results

One month after the amputation the informants described and related their phantom pain and phantom sensations in sensory-discriminative, motivational-affective and cognitive-evaluative dimensions. The phantom sensations were experienced mainly as more agonizing than the phantom pain.

Despite both the high intensity of and the high annoyance at the phantom pain and phantom sensations, a majority felt that the phantom phenomena were not a hindrance in their attempts to recapture ordinary life. But when the hindrance was evaluated as high, the annoyance was evaluated as the highest possible for both phenomena or for the phantom sensations alone, never for phantom pain alone. The interviewees’ reported attitudes of hindrance were also described and estimated in the light of their sociocultural circumstances. Thus, other preceding and/or co-existent pain conditions as well as factors such as pre-operative information, the respondents’ views on pain treatment, and their knowledge and understanding of phantom phenomena were mentioned and related to the pain-producing situation.

Two-thirds of the interviewees had received post-surgical information and for some, the phenomena were well-known from earlier experience. A majority applied some version of the medical explanation model, irrespective of age or level of education. However neither information nor medical explanation, or both, sufficed for them to understand their own phantom phenomena. Thus, differences between the concepts explanation and understanding seemed significant for the annoyance related to the phantom phenomena.

Regarding background data

(i) the majority of the interviewees had had pre-amputation pain problems; (ii) the breast-cancer phantoms differed in several ways; (iii) there were some age and gender differences in the descriptions of hindrance.

Conclusions and implications

These findings highlight the importance of observing the individual approach to the phenomena as a process of evaluation and selection. In addition, experience and understanding of the phantoms also have sociocultural aspects. There follows the need for individualized communication and information from the clinician, and for incorporating a socioscientific and meaning-centred approach in future studies. The present insights could also be of value in other iatrogenic pain conditions.

Item selection in self-report measures for children and adolescents with disabilities: lessons from cognitive interviews

The aim of the study was to evaluate children's and adolescents' understanding of items from self-report measures. Cognitive interviews were conducted as part of a larger study on pain and fatigue in children with disabilities. A list of guiding questions was used to encourage participants to talk about words or concepts in the scale that they found difficult. The sample included 32 children and adolescents with physical disabilities. Participants had difficulty with words such as intense, severe, and anxiety. They had more difficulty with abstract ideas, such as average, than they did with more concrete ideas, such as naming a recreational or social activity. Because poor outcome measurement hinders symptom evaluation, findings support the need to put greater emphasis on the child perspective when developing and using self-report measures. Suggestions for increasing accuracy of these measures are offered for clinicians and researchers.

Mirror-sensory synaesthesia: exploring 'shared' sensory experiences as synaesthesia

Recent research suggests the observation or imagination of somatosensory stimulation in another (e.g., touch or pain) can induce a similar somatosensory experience in oneself. Some researchers have presented this experience as a type of synaesthesia, whereas others consider it an extreme experience of an otherwise normal perception. Here, we present an argument that these descriptions are not mutually exclusive. They may describe the extreme version of the normal process of understanding somatosensation in others. It becomes synaesthesia, however, when this process results in a conscious experience comparable to the observed person's state. We describe these experiences as 'mirror-sensory synaesthesia'; a type of synaesthesia identified by its distinct social component where the induced synaesthetic experience is a similar sensory experience to that perceived in another person. Through the operationalisation of this intriguing experience as synaesthesia, existing neurobiological models of synaesthesia can be used as a framework to explore how mechanisms may act upon social cognitive processes to produce conscious experiences similar to another person's observed state.

Phantom limb pain: mechanisms and treatment approaches

The vast amount of research over the past decades has significantly added to our knowledge of phantom limb pain. Multiple factors including site of amputation or presence of preamputation pain have been found to have a positive correlation with the development of phantom limb pain. The paradigms of proposed mechanisms have shifted over the past years from the psychogenic theory to peripheral and central neural changes involving cortical reorganization. More recently, the role of mirror neurons in the brain has been proposed in the generation of phantom pain. A wide variety of treatment approaches have been employed, but mechanism-based specific treatment guidelines are yet to evolve. Phantom limb pain is considered a neuropathic pain, and most treatment recommendations are based on recommendations for neuropathic pain syndromes. Mirror therapy, a relatively recently proposed therapy for phantom limb pain, has mixed results in randomized controlled trials. Most successful treatment outcomes include multidisciplinary measures. This paper attempts to review and summarize recent research relative to the proposed mechanisms of and treatments for phantom limb pain.

The menacing phantom: what pulls the trigger?

Phantom phenomena are frequent following amputation, but how this often painful experience is modified or triggered by spontaneous events or sensations often puzzles amputees and clinicians alike. We explored triggers of phantom phenomena in a heterogeneous sample of 264 upper and lower limb adult amputees with phantom sensations. Participants completed a structured questionnaire to determine the prevalence and nature of the triggers of phantom phenomena. The four categories of triggers identified include: (a) a quarter of participants experiencing psychological, emotional or autonomic triggers; (b) half experiencing behavioral triggers, "forgetting" the limb's absence and attempting to use the phantom; (c) one-fifth experiencing weather-induced triggers; and (d) one-third experiencing sensations referred from parts of the body. Upper limb amputees; and were more likely to experience weather-induced phantom phenomena than lower limb amputees; and upper and lower limb amputees were equally likely to experience referred sensations from the genitals, contradicting the homuncular remapping hypothesis. Traumatic amputees were more likely to report emotional triggers. Further, while those with emotional triggers exhibited poorer acceptance of the limitations of amputation, they were more likely to employ adaptive coping mechanisms. Finally, habitual "forgetting" behaviors were most common soon after amputation, whereas other more adaptive schemata (e.g., self-defense) were equally likely to be performed at any time following amputation. Various likely inter-related mechanisms are discussed in relation to phantom triggers. Ultimately, optimizing stump and neuroma management, as well as restoring function of central networks for pain, limb movement, and amputation-related memories, should help manage spontaneously triggered phantom phenomena.

Supernumerary phantom limbs in spinal cord injury

STUDY DESIGN AND OBJECTIVES

Case report and review of supernumerary phantom limbs in patients suffering from spinal cord injury (SCI).

SETTING

SCI rehabilitation centre.

CASE REPORT

After a ski accident, a 71-year-old man suffered an incomplete SCI (level C3; AIS C, central cord syndrome), with a C3/C4 dislocation fracture. From the first week after injury, he experienced a phantom duplication of both upper limbs that lasted for 7 months. The supernumerary limbs were only occasionally related to painful sensation, specifically when they were perceived as crossed on his trunk. Although the painful sensations were responsive to pain medication, the presence of the illusory limb sensations were persistent. During neurological recovery, the supernumerary limbs gradually disappeared. A rubber hand illusion paradigm was used twice during recovery to monitor the patient's ability to integrate visual, tactile and proprioceptive stimuli.

CONCLUSION

Overall, the clinical relevance of supernumerary phantom limbs is not clear, specific treatment protocols have not yet been developed, and the underlying neural mechanisms are not fully understood. Supernumerary phantom limbs have been previously reported in patients with (sub)cortical lesions, but might be rather undocumented in patients suffering from traumatic SCI. For the appropriate diagnosis and treatment after SCI, supernumerary phantoms should be distinguished from other phantom sensations and pain syndromes after SCI.

Adult limb and breast amputees’ experience and descriptions of phantom phenomena—A qualitative study

Background

Phantom phenomena – pain or other sensations appearing to come from amputated body parts – are frequent consequences of amputation and can cause considerable suffering. Also, stump pain, located in the residual limb, is in the literature often related to the phantom phenomena. The condition is not specific to amputated limbs and has, to a lesser extent, been reported to be present after radical surgery in other body parts such as breast, rectum and teeth.

Multi-causal theories are used when trying to understand these phenomena, which are recognized as the result of complex interaction among various parts of the central nervous system confirmed in studies using functional brain imaging techniques.

Functional brain imaging has yielded important results, but without certainty being related to phantom pain as a subjective clinical experience.

There is a wide range of treatment methods for the condition but no documented treatment of choice.

Aims

In this study a qualitative, explorative and prospective design was selected, in the aim to understand the patients’ personal experience of phantom phenomena.

The research questions focused at how patients affected by phantom pain and or phantom sensations describe, understand, and live with these phenomena in their daily life.

This study expanded ‘phantom phenomena’ to also encompass phantom breast phenomenon. Since the latter phenomenon is not as well investigated as the phantom limb, there is clinical concern that this is an underestimated problem for women who have had breasts removed.

Methods

The present study forms the first part of a larger, longitudinal study. Only results associated with data from the first interviews with patients, one month after an amputation, are presented here. At this occasion, 28 patients who had undergone limb amputation (20) or mastectomy (8) were interviewed. The focused, semi-structured interviews were recorded, transcribed, and then analyzed using discourse-narrative analysis.

Results

The interviewees had no conceptual problems in talking about the phenomena or distinguishing between various types of discomfort and discomfort episodes. Their experience originated from a vivid, functioning body that had lost one of its parts. Further, the interviewees reported the importance of rehabilitation and advances in prosthetic technology. Loss of mobility struck older amputees as loss of social functioning, which distressed them more than it did younger amputees. Phantom sensations, kinetic and kinesthetic perceptions, constituted a greater problem than phantom pain experienced from the amputated body parts. The descriptions by patients who had had mastectomies differed from those by patients who had lost limbs in that the phantom breast could be difficult to describe and position spatially.

The clinical implication of this study is that when phantom phenomena are described as everyday experience, they become a psychosocial reality that supplements the definition of phantom phenomena in scientific literature and clinical documentation.

Conclusions

There is a need for clinical dialogues with patients, which besides, providing necessary information about the phenomena to the patients creates possibilities for health professionals to carefully listen to the patients’ own descriptions of which functional losses or life changes patients fear the most. There is a need for more qualitative studies in order to capture the extreme complexity of the pain–control system will be highlighted.

Painful and nonpainful phantom and stump sensations in acute traumatic amputees

BACKGROUND

The formation, prevalence, intensity, course, and predisposing factors of phantom limb pain were investigated to determine possible mechanisms of the origin of phantom limb pain in traumatic upper limb amputees.

METHODS

Ninety-six upper limb amputees participated in the study. A questionnaire assessed the following question: side, date, extension, and cause of amputation; preamputation pain; and presence or absence of phantom pain, phantom and stump sensations or stump pain or both.

RESULTS

The response rate was 84%. Sixty-five (81%) participants returned the questionnaire. In 64 (98.5%) participants a traumatic injury led to amputation; the amputation was necessary because of infection in one patient (1.5%). The median follow-up time (from amputation to evaluation) was 3.2 years (range, 0.9-3.8 years) The prevalence of phantom pain was 44.6%, phantom sensation 53.8%, stump pain 61.5%, and stump sensation 78.5%. After its first appearance, phantom pain had a decreasing course in 14 (48.2%) of 29 amputees, was stable in 11 (37.9%) amputees, and worsened in 2 (6.9%) of 29 amputees. Stump pain had a decreasing course in 19 (47.5%) of 40 amputees but was stable in 12 (30%) amputees. Phantom pain occurred immediately after amputation in 8 (28%) of 29 amputees between 1 month and 12 months in 3 (10%) amputees and after 12 or more months in 12 (41%) amputees.

CONCLUSION

Stump pain and stump sensation predominate traumatic amputees' somatosensory experience immediately after amputation; phantom pain and phantom sensations are often long-term consequences of amputation. Amputees experience phantom sensations and phantom pain within 1 month after amputation, a second peak occurs 12 months after amputation. Revised diagnostic criteria for phantom pain are proposed on the basis of these data.

Nursing aspects of phantom limb pain following amputation

Phantoms (painless and painful) occur following the removal of virtually all body parts. Phantoms of the limbs, including phantom limb pain (PLP), are the most studied. As yet there is no agreed theory to explain phantom limb pain but the neuromatrix and cortical reorganization theories have come to prominence over recent years. Multiple treatment strategies have been applied to PLP; however, none of these strategies have been proven to be effective for the majority of amputees. As a result of knowledge acquired through the cortical reorganization theory, new avenues for treatment have opened up. These include pre-emption and normalization strategies which have significant nursing aspects. This article explores all of these issues and identifies the implications that they have for the nursing treatment of patients with PLP and those that are expected to develop it. This involves the care of people pre-, peri- and post-amputation. All aspects of phantoms and phantom pain need to be taken into account by nurses and other healthcare workers when planning rehabilitation packages for this group.

Pain in children: recent advances and ongoing challenges

Significant advances in the assessment and management of acute pain in children have been made, and are supported by an increase in the availability and accessibility of evidence-based data. However, methodological and practical issues in the design and performance of clinical paediatric trials limit the quantity, and may influence the quality, of current data, which lags behind that available for adult practice. Collaborations within research networks, which incorporate both preclinical and clinical studies, may increase the feasibility and specificity of future trials. In early life, the developing nervous system responds differently to pain, analgesia, and injury, resulting in effects not seen in later life and which may have long-term consequences. Translational laboratory studies further our understanding of developmental changes in nociceptor pathway structure and function, analgesic pharmacodynamics, and the impact of different forms of injury. Chronic pain in children has a negative impact on quality of life, resulting in social and emotional consequences for both the child and the family. Despite age-related differences in many chronic pain conditions, such as neuropathic pain, management in children is often empirically based on data from studies in adults. There is a major need for further clinical research, training of health-care providers, and increased resources, to improve management and outcomes for children with chronic pain.

A randomised double blind trial of the effect of pre-emptive epidural ketamine on persistent pain after lower limb amputation

Persistent pain has been reported in up to 80% of patients after limb amputation. The mechanisms are not fully understood, but nerve injury during amputation is important, with evidence for the crucial involvement of the spinal N-methyl d-aspartate (NMDA) receptor in central changes. The study objective was to assess the effect of pre-emptively modulating sensory input with epidural ketamine (an NMDA antagonist) on post-amputation pain and sensory processing. The study recruited 53 patients undergoing lower limb amputation who received a combined intrathecal/epidural anaesthetic for surgery followed by a randomised epidural infusion (Group K received racemic ketamine and bupivacaine; Group S received saline and bupivacaine). Neither general anaesthesia nor opioids were used during the peri-operative period. Pain characteristics were assessed for 12 months. The primary endpoint was incidence and severity of post-amputation pain. Persistent pain at one year was much less in both groups than in comparable studies, with no significant difference between groups (Group K=21% (3/14) and 50% (7/14); and Group S=33% (5/15) and 40% (6/15) for stump and phantom pain, respectively). Post-operative analgesia was significantly better in Group K, with reduced stump sensitivity. The intrathecal/epidural technique used, with peri-operative sensory attenuation, may have reduced ongoing sensitisation, reducing the overall incidence of persistent pain. The improved short-term analgesia and reduced mechanical sensitivity in Group K may reflect acute effects of ketamine on central sensitisation. Longer term effects on mood were detected in Group K that requires further study.

Central mechanisms in phantom limb perception: The past, present and future

Phantom limbs provide valuable insight into the mechanisms underlying bodily awareness and ownership. This paper reviews the complexity of phantom limb phenomena (proprioception, form, position, posture and telescoping), and the various contributions of internal constructs of the body, or body schema, and neuromatrix theory in explaining these phenomena. Specific systems and processes that have received little attention in phantom limb research are also reviewed and highlighted as important future directions, These include prosthesis embodiment and extended physiological proprioception (i.e., the extension of the body's "area of influence" that thereby extends one's innate sense of proprioception, mirror neurons and cross-referencing of the phantom limb with the intact limb (and the related phenomena of perceiving referred sensations and mirrored movements in the phantom form the intact limb). The likely involvements of the body schema and the body-self neuromatrix, mirror neurons, and cross-callosal and ipsilateral mechanisms in phantom limb phenomena all suggest that the perception of a "normal" phantom limb (that is, a non-painful phantom that has the sensory qualities of an intact limb) is more than likely an epiphenomenon of normal functioning, action understanding and empathy, and potentially may even be evolutionarily adaptive and perhaps necessary. Phantom pain, however, may be a maladaptive failure of the neuromatrix to maintain global bodily constructs.